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1.
Huaan Yang Daniel Renshaw Geoff Thomas Bevan Buirchell Mark Sweetingham 《Molecular breeding : new strategies in plant improvement》2008,21(4):473-483
A key challenge in marker-assisted selection (MAS) for molecular plant breeding is to develop markers linked to genes of interest
which are applicable to multiple breeding populations. In this study representative F2 plants from a cross Mandalup (resistant to anthracnose disease) × Quilinock (susceptible) of Lupinus angustifolius were used in DNA fingerprinting by Microsatellite-anchored Fragment Length Polymorphism (MFLP). Nine candidate MFLP markers
linked to anthracnose resistance were identified, then ‘validated’ on 17 commercial cultivars. The number of “false positives”
(showing resistant-allele band but lack of the R gene) for each of the nine candidate MFLP markers on the 17 cultivars ranged
from 1 to 9. The candidate marker with least number of false positive was selected, sequenced, and was converted into a co-dominant,
sequence-specific, simple PCR based marker suitable for routine implementation. Testing on 180 F2 plants confirmed that the converted marker was linked to the R gene at 5.1 centiMorgan. The banding pattern of the converted
marker was consistent with the disease phenotype on 23 out of the 24 cultivars. This marker, designated “AnManM1”, is now
being used for MAS in the Australian lupin breeding program. We conclude that generation of multiple candidate markers, followed
by a validation step to select the best marker before conversion to an implementable form is an efficient strategy to ensure
wide applicability for MAS. 相似文献
2.
α-Glucosidase is a catabolic enzyme that regulates the body’s plasma glucose levels by providing energy sources to maintain healthy functioning. 2-Amino-thiadiazole (1–13) and 2-amino-thiadiazole based Schiff bases (14–22) were synthesized, characterized by 1H NMR and HREI-MS and screened for α-glucosidase inhibitory activity. All twenty-two (22) analogs exhibit varied degree of α-glucosidase inhibitory potential with IC50 values ranging between 2.30 ± 0.1 to 38.30 ± 0.7 μM, when compare with standard drug acarbose having IC50 value of 39.60 ± 0.70 μM. Among the series eight derivatives 1, 2, 6, 7, 14, 17, 19 and 20 showed outstanding α-glucosidase inhibitory potential with IC50 values of 3.30 ± 0.1, 5.80 ± 0.2, 2.30 ± 0.1, 2.70 ± 0.1, 2.30 ± 0.1, 5.50 ± 0.1, 4.70 ± 0.2, and 5.50 ± 0.2 μM respectively, which is many fold better than the standard drug acarbose. The remaining analogs showed good to excellent α-glucosidase inhibition. Structure activity relationship has been established for all compounds. The binding interactions of these compounds were confirmed through molecular docking. 相似文献
3.
The diversity and distribution of modern benthic foraminifera has been extensively studied in order to aid the paleoecological
interpretation of their fossil record. Traditionally, foraminiferal species are identified based on morphological characters
of their organic, agglutinated or calcareous tests. Recently, however, new molecular techniques based on analysis of DNA sequences
have been introduced to study the genetic variation in foraminifera. Although the number of species for which DNA sequence
data exist is still very limited, it appears that morphology-based studies largely underestimated foraminiferal diversity.
Here, we present two examples of the use of DNA sequences to examine the diversity of benthic foraminifera. The first case
deals with molecular and morphological variations in the well-known and common calcareous genus Ammonia. The second case presents molecular diversity in the poorly documented group of monothalamous (single-chambered) foraminifera.
Both examples perfectly illustrate high cryptic diversity revealed in almost all molecular studies. Molecular results also
confirm that the majority of foraminiferal species have a restricted geographic distribution and that globally distributed
species are rare. This is in opposition to the theory that biogeography has no impact on the diversity of small-sized eukaryotes.
At least in the case of foraminifera, size does not seem to have a main impact on dispersal capacities. However, the factors
responsible for the dispersal of foraminiferal species and the extension of their geographic ranges remain largely unknown.
Special Issue: Protist diversity and geographic distribution. Guest editor: W. Foissner. 相似文献
4.
土壤镉污染对大蒜幼苗生长及根系抗氧化系统的影响 总被引:2,自引:0,他引:2
通过土培实验研究了镉污染胁迫对大蒜幼苗生长及根系抗氧化系统的影响.结果表明:与对照组比较,土壤低浓度镉对大蒜幼苗生长略有促进作用,单株鲜质量、干质量、根长及地上部分高度略有增加,而根系活力、可溶性蛋白含量、超氧化物坡化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性显著升高,抗氧化防御酶系统仍保持平衡,表现在膜脂质过氧化产物(MDA)含量与对照组无明显差异;但随着土壤镉浓度的进一步增加,大蒜平均单株鲜质量、干质量、平均最大根长及地上部分高度均显著降低,同时,根系活力和可溶性蛋白含量增幅逐渐减弱,抗氧化防御酶系统平衡受到破坏,根系MDA含量显著上升.大蒜对镉吸收积累主要在根部,而向地上部分转运较少. 相似文献
5.
《Saudi Journal of Biological Sciences》2017,24(6):1327-1335
A large-scale field survey was conducted to screen major Saudi Arabian beekeeping locations for infection by Melissococcus plutonius. M. plutonius is one of the major bacterial pathogens of honeybee broods and is the causative agent of European Foulbrood disease (EFB). Larvae from samples suspected of infection were collected from different apiaries and homogenized in phosphate buffered saline (PBS). Bacteria were isolated on MYPGP agar medium. Two bacterial isolates, ksuMP7 and ksuMP9 (16S rRNA GenBank accession numbers, KX417565 and KX417566, respectively), were subjected to molecular identification using M. plutonius -specific primers, a BLAST sequence analysis revealed that the two isolates were M. plutonius with more than 98% sequence identity. The molecular detection of M. plutonius from honeybee is the first recorded incidence of this pathogen in Saudi Arabia. This study emphasizes the need for official authorities to take immediate steps toward treating and limiting the spread of this disease throughout the country. 相似文献
6.
《Bioorganic & medicinal chemistry》2014,22(22):6503-6508
c-myc G-quadruplex DNA, which plays a central role in tumor progression and resistance, has been extensively investigated as potential target of antitumor drugs. In this paper, a series of phenanthroimidazole derives have been synthesized under irradiation of microwave in yields of 51–80%. The antitumor activity of these compounds against various tumor cells has been evaluated, and the results show that these compounds exhibit great inhibition to MDA-MB-231, MCF-7 and Hela cells, especially 5 inhibit the growth of MDA-MB-231 cells with IC50 about 3.6 μM. The further studies show that 5 can bind and stabilize c-myc G4 DNA in π–π stacking mode, which confirmed by the hypochromise in the electronic spectra of 5 with the increasing of c-myc G4 DNA. When dealt with 5, the strength of CD signal attributed to c-myc G4 DNA is decreased and the FRET melting point of c-myc G4 DNA is increased. Moreover, the molecule docking calculation was conducted to show that 5 suitably stack onto the 5′ G-quartet surface, and parallels to the surfaces of the G5 and G-quartet consisting of G7, G11, G16, and G20. As a result, the replication of c-myc oligomers is blocked by 5. In a word, this type of phenanthroimidazole derives can act as potential inhibitor against breast cancer cells by binding and stabilizing c-myc G4 DNA through π–π stacking. 相似文献
7.
《Bioorganic & medicinal chemistry》2014,22(21):6174-6182
Upon reacting 3′,4′-unsaturated cytosine (8 and 9) and adenine nucleosides (13 and 14) with XeF2/BF3·OEt2, the respective novel 3′,4′-difluoro-3′-deoxyribofuranosyl nucleosides (10–12 and 15–18) could be obtained. Formation of anti-adducts (11, 16 and 18) revealed that the fluorination involved oxonium ions as incipient intermediates. TBDMS-protected 3′,4′-unsaturated adenosine provided the β-face adducts as sole stereoisomers whereas α-face-selectivity was observed with the TBDPS-protected adenosine 14. The evaluation of the novel 3′-deoxy-3′,4′-difluororibofuranosylcytosine-(19–21) and adenine nucleosides (22–25) against antitumor and antiviral activities revealed that 3′,4′-difluorocordycepin (24) was found to possess anti-HCV activity. The SI of 24 was comparable to that of the anti-HCV drug ribavirin. However, sofosbuvir, FDA-approved novel anti-HCV drug, showed better SI value. Our finding revealed that the introduction of the fluoro-substituent into the 4′-position of cordycepin derivatives decreased the cytotoxicity to the host cell with retention of the antiviral activity. 相似文献
8.
Two new myrmecophilous species of the genus Scutacarus (Acari: Prostigmata: Scutacaridae) with world keys to related species groups 下载免费PDF全文
In a survey on heterostigmatic mites (Acari: Prostigmata: Heterostigmata) associated with insects including ants in northwestern Iran, two new species of myrmecophilous mites of the genus Scutacarus (Acari: Scutacaridae) were found. They are S. shajariani sp. nov. phoretic on Tetramorium sp. (Hymenoptera: Formicidae) and S. ebermanni sp. nov. phoretic on Messor sp. The mentioned new species belong to groups of species with reduced setae e and h2, and no setae 4b, respectively. These two new species are described and illustrated, and world keys are provided for respective species groups. 相似文献
9.
Ehsan Ullah Mughal Amina Sadiq Shahzad Murtaza Hummera Rafique Muhammad Naveed Zafar Tauqeer Riaz Bilal Ahmad Khan Abdul Hameed Khalid Mohammed Khan 《Bioorganic & medicinal chemistry》2017,25(1):100-106
The present study describes efficient and facile syntheses of varyingly substituted 3-thioaurones from the corresponding 3-oxoaurones using Lawesson’s reagent and phosphorous pentasulfide. In comparison, the latter methodology was proved more convenient, giving higher yields and required short and simple methodology. The structures of synthetic compounds were unambiguously elucidated by IR, MS and NMR spectroscopy. All synthetic compounds were screened for their inhibitory potential against in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Molecular docking studies were also performed in order to examine their binding interactions with AChE and BChE human proteins. Both studies revealed that some of these compounds were found to be good inhibitors against AChE and BChE. 相似文献
10.
《Harmful algae》2015
Marine benthic dinoflagellates within the genus Coolia have been reported to produce natural products, some of which are known to be toxic (i.e., cooliatoxin). To date, five species of Coolia have been reported in tropical and temperate waters around the world; however, very few studies have combined detailed morphological and molecular data with chemical analyses. In this study, a clonal culture of Coolia malayensis was isolated and mass cultivated from a coral reef on the island of Okinawa, Japan. Analysis of the thecal plate morphology and molecular phylogeny from 28S rDNA strongly supported the close relationship between this new isolate of C. malayensis from Okinawa and other isolates of C. malayensis from around the world. Following methanol extraction of 250 L of mass culture, chemical analyses using NanoLiquid chromatography mass spectrometry revealed the mass profiles of water-soluble and ethyl acetate-soluble parts. High-resolution mass spectrometry derived the molecular formulas of three novel disulphated polyether analogs of yessotoxin (C56H78O18S2 1102.4 (Compound 1), C57H80O18S2 1116.4 (Compound 2), and C57H78O19S2 1130.4 (Compound 3)); two potential homologous compounds (Compounds 4 and 5) were also observed on the high-resolution mass, albeit with low signal intensity. The five compounds in the C. malayensis from Okinawa are composed of less oxygen, compared to cooliatoxin and other analogs of yessotoxin, suggesting the metabolites produced by C. malayensis are unique to those previously reported from other strains of Coolia. 相似文献